docs: def save_nifti(filename, obj, like=None, header=None, affine=None, extensions=Ellipsis, version=1):
      '''
      save_nifti(filename, obj) saves the given object to the given filename in the nifti format and
        returns the filename.
  
      All options that can be given to the to_nifti function can also be passed to this function; they
      are used to modify the object prior to exporting it.   
      '''
      obj = to_nifti(obj, like=like, header=header, affine=affine, version=version,
                     extensions=extensions)
      obj.to_filename(filename)
      return filename